Needle-operating mechanism for grain-binders.



No. 653,405. Pate nted July 10,1900 H. B. SPERBY. NEEDLE OPERATING MEGHANISM FUR GRAIN BINDERS.

(No Model.)

UNITED STAT S PATENT OFFICE.

HERBERT B. SPERRY, OF SPRINGFIELD, OHIO.

NEEDLE-OPERATING MECHANISM FOR GRAIN-BINDERS.

SPECIFICATION forming part of Letters Patent No. 653,405, dated July 10, 1900. Applioationfiled December 14, 1899. Serial. No. 740,236. (No model.)

needle-actuatin g mechanism according to the requirements of the compressing operation.

A further object of the invention is to provide means whereby the Variations of power exerted by the mechanism which actuates the needle-operating pitman is compensated by varying the leverage exerted by said pitman upon the needle-shaft crank-arm.

Other objects of the invention will appear more fully hereinafter.

The invention consists, substantially,in the construction, combination, location, and arrangement, all as will be more fully hereinafter set forth, as shown in the accompanying drawings, and finally pointed out in the'ap- I pended claims.

Referring to the accompanying drawings and to the various views and reference-signs appearing thereon, Figure l is a broken detail View, in side elevation, of a portion of a grainbinder, showing the application thereto of a construction embodying the principles of my invention, the needle being shown in its advanced position. showing the needle in retracted position.

In Patent No. 467,467, issued January 19, 1892, to Maurice Kane, is shown, described, and claimed a construction of needle-operating mechanism for grain-binders,wherein the power of the needle-operating pitman is increased as the needle is advanced to its work by reason of an increasing leverage through which the pitman'effects the advancement of the needle. In the construction disclosed in said patent the needle-operating pitman is connected to a crank-arm on the needle-shaft through a block mounted to slide in a slot Fig. 2 is a similar view,-

formed in said crank-arm, and a rod is connected at one end to said block and at the other end to a convenient part of the framework, whereby when the pitman is operated to effect the advancing movement of the needle said block is moved outwardly in the slot in the crank-arm, thereby increasing the leverage exerted by said pitman through said crank-arm,'and hence increasing the power of the needle as it advances to its work.

In the usual operation of mechanism of this class it is the custom to pivotally connect the pitm an eccentrically to a main operating gear or wheel,and hence during the rotation of such wheel the power exerted thereby upon the pitman varies according to the position of thepoint of pivotal connection of the pitman to such gear. Forinstance,in the position of the parts as shown in Fig. l of the drawings the pitman exerts it maximum power by reason of the fact that the line of thrust or pull of said pitman is transverse to the axis of rotation of its operating-gear. From this point the power of the pitman begins to decrease during the next quarter-revolution of the operatinggear--that is, during the approach of the point of connection of the pitman to its operatinggear to a position such as to cause the pitman to stand'at right angles to a radius of the gear 'passin g through such point of pivotal connec- During the second quarter of the revolution of said operating-gear the point of connection of the'pitman thereto approaches parallelism,

with the radius passing through such point, and hence the power of the pitmanis increasin g. The parts are now in the position shown in Fig. 2that is, the needle is in its retracted position. The gavel is now formed in the usual manner and the needle mechanism is placed in operation. During the third quarter of the revolution ofthe operating-gear-that is, that portion of the revolution of said gear which effects the initial advancing movement of'the needle from the position shown in Fig. 2the point of connection of the pitman to the operating-gear is approaching a position such as to causeithe pitman to be at right angles to the radius passing through such point, and hence its power is decreasing. During the fourth revolution of the operating-gear to complete the advancing movement of the needle the power of the pitman is again increasing. Thus it will be seen that the power of the pitman varies during that half of the complete rotation of its operating-wheel which carries the pitman from the position shown in Fig. 2 to that shown in Fig. 1, such power gradually decreasing up to the time the pitman stands at right angles to the radius passing through the point of pivotal connection thereof to the gear and then increasing again until the needle is fully advanced. In said prior patent no account is taken of this variation in the power exerted by the pitman, buta construction is provided therein which effects a constantly-increasing leverage of such pitman upon the needle-operating shaft irrespective of the variations in power exerted upon the pitman by its operating-gear, and hence power is wasted by reason of the fact that the increase in power of the pitman is not compensated by a corresponding variation in the leverage exerted thereby upon the needlecran-k. In other words, the increase in leverage is constant, and is not varied to accommodate or compensate for the variations in power of the pitman.

It is. the special purpose of the present invention to provide a construction wherein the increase in leverage is varied according to thevariations in the power of the pitman, the leverage increasing in proportion to the decrease in power of the pitman and decreasing in proportion to the increase in power of the pitman, thusutilizing the power required to accomplish the work in the most efficient manner;

Referring to-th-e drawings, wherein is illustrated. a construction embodying the princi- PlBSzOf my invention, A designates the needle; B, the needle-shaft; C, the crank-arm on said shaft; D, the pitman, and E the gear for operating the pitman and eecentrically upon the face of which is pivotally connected one end of the pitman, as at F, said pitman being connected to the crank-arm O. In said prior patent this connection is effected by pivotall-y connecting the end of the pitman to a. block mounted to slide in a slot arranged to extend longitudinally of the crank-arm, a rod being connected at one end to said block and at the other end to a convenient part of the framework of the machine, whereby as the crank-arm is rocked through the actuation of the pitman to advance the needle its point of connection to said crank-arm is shifted, therebyeifecting an increasing leverage. In the present invention I employ the pivotal connection of the pitman to the crank-arm, also the feature of a slot in the crank-arm, in

whichsaid pivotal connection moves, and also the feature of a rod (indicated at G) connected at one end to a convenient part of the frame and at the other end to the pitman or to its point of connect-ion with the crank-arm; but in said prior patent the slot in the crank-arm extended lengthwise of such. arm, and hence during the advancing movement of' the needle the leverage is constantly-and steadily in creased, thereby losing the advantage to be derived from the variation in the power exerted upon the pitman D by its operating-gear E, as above explained. In order to avoid this loss and to utilize to the fullest extent all the power required for accomplishing the work, I form the slot in the crank-arm intoa cam or curved slot, as clearly shown, the degree of curvature and the particular shape of the slot being suitably proportioned to compensate and correspond approximately reciprocally to the variations in power exerted by the pitman-actuating gear during that part of the movement thereof which eilects the advancing movement of the needle. To this end the portion II of the curved slot is so shaped that it effects a comparatively-rapid movement of the block or roller J, to which the pitman is pivotally connected and which rides in said slot toward the outer end of the crank-arm during that portion of the rotation of operating-gear E which carries the pitman into or toward a position at right angles to a radius of such wheel passing through the point F. Therefore in proportion as the pitman loses power by reason of the changing position of the point of connection thereof with the gearE the leverage of the pitman exerted. through crank-arm 0 increases, this 7 approximatelyproportional relation not being secured when the slot in the crank-arm is straight. This relative increase of leverage as the power decreases is maintained until the power again begins to increase. This point is reached after the gear Ehasrevolved a quarter of a revolution from the position shown in Fig. 2 and begins to approach that shown in Fig. 1, and from this point on and until the position shown in Fig. 1 is reached the power of the pitman is increasing, and

' hence to utilize this increasing power to the greatest advantage the increase in leverage I therefore form the perof the-block or connection J, through theportion II of the cam or curved slot during the initial stages of the advancing movement of; the needle, causes said block or connection to move rapidly away from the axis of shaft iB, thereby rapidly increasing the leverage;v

but the travel of said block or connection along the reversely-curved portion K of theslot causes only a slight movement of said block or connection away from the axis of shaft B, and hence there will be only slight. increase in leverage.

that I provide a construction wherein the in Thus it will be seen crease or variation in leverage exerted by the pitman on the needle-actuating shaft is approximately in reciprocal proportion to the variation of power exerted by the pitman. It is obvious that this result may be accomplished in many other specifically-diiferent ways and still fall within the spirit and scope of my invention. I do not desire, therefore, to be limited or restricted to the exact construction shown and described; but,

Having now set forth the object and nature of my invention and a form of construction embodying the principles thereof and having explained its functions and mode of operation, what I claim as new and useful and of my own invention, and desire to secure by Letters Patent, is-

1. In a grain-binder, a needle-shaft and needle, a crank-arm connected to said shaft, a pitman connected at one end to said crankarm, an operating-gear to which the other end of said pitman is connected, and means for automatically moving the crank-arm connection of said pitman along said crank-arm to vary the leverage of said pitman upon said crank-arm in approximately-reciprocal proportion to the variation of power exerted by said gear upon said pitman, as and for the purpose set forth.

2. In a grain-binder, aneedle-shaft and needle, a crank-arm mounted on said shaft, an operating-gear, a pitman connected at one end to said operating-gear and at the other end connected to said crank-arm, and means for moving the crank-arm connection of said pitman along the crank-arm to vary the leverage exerted by said pitman approximately in reciprocal proportion to the variation in power exerted by said drive-gear upon said pitman, as and for the purpose set forth.

3. In a grain-binder, aneedle-shaft and needle, a crank-arm connected to said shaft, said crank-arm provided with a curved slot, a pitman engaging in said curved slot, an operatin g-gear for said pitman, and a rod connected to the framework and to said pitman for moving the crank-arm connection of said pitman along the slot in said crank-arm, to vary the leverage exerted by the pitman upon the crank-arm in approximately-reciprocal proportion to the variation in power exerted by said operating-gear, as and for the purpose set forth.

4. In a grain-binder, a needle-shaft and needle, a crank-arm connected to said shaft and provided with a slot, said slot having a reversely-curved portion, a pitman engaging in said slot, an operating-gear for said pitman, and a rod connected to the framework and to said pitman for moving the crank-arm connection of said pitman along the slot in said crank-arm, to vary the leverage exerted by the pitman upon the crank-arm in approximately-reciprocal proportion to the variation in power exerted by said operating-gear, as and for the purpose set forth.

5. In a grain-binder, a needle-shaft and needle, a crank-arm connected to said shaft and provided with a curved slot, a pitman carrying a projection arranged to extend into said slot, an operating gear-wheel to which said pitman is eccentrically connected, and a rod connected at one end to the framework and at the other end to the projection carried by the pitman, for moving said projection along said slot to vary the leverage exerted by the pitman upon said crank-arm in approximately-reciprocal proportion to the variation in power exerted by said drive-gear, as and for the purpose set forth.

In witness whereof I have hereunto set my hand, this 7th day of December, 1899, in the presence of the subscribing witnesses.

. HERBERT B. SPERRY.

Witnesses:

W. B. EDGAR, HENRY O. DIMOND. 

